* HDLC stands for High-Level Data Link Control protocol. It is the property protocol of Cisco which is the default encapsulation operated with Cisco routers.
* HDLC is a bit-oriented protocol that supports both half and full duplex communication.
* HDLC adds the information in a data frame that allows the devices to control the data flow.
* HDLC offers flexibility, adaptability, reliability, and efficiency of operation for synchronous data communication.
* It supports both point-to-point and point-to-multipoint communication.
* It supports synchronous as well as asynchronous communication.
* It provides full data transparency, i.e., the output delivered has the same bit sequence as the input without any restriction.
